The superconducting magnet development for the next generation ECR ion source on LEAF

In December 2024, the world first stand-alone Low Energy high intensity heave ion Accelerator Facility (LEAF) has been commissioned to its design performance and passed the acceptance test conducted by the National Natural Science Foundation of China. LEAF is designed and built by the Institute of Modern Physics, CAS, which is aiming to provide unprecedent ion beam conditions for the researches of nuclear astrophysics, atomic physics, nuclear materials and so on. To realize this goal, it is essential to develop an ECR (Electron Cyclotron Resonance) ion source beyond the performance of the state-of-the-art machines. This ECR ion source is called FECR (First 4th generation ECR ion source) designed to be operated with the plasma heated by 45 GHz microwave frequency that needs high magnetic field confinement. Therefore, with FECR Nb 3 Sn superconducting technology was incorporated to ECR ion source for the first time in the world. FECR features Nb 3 Sn solenoids and NbTi sextupole coils that enables its high performing operation at 45 + 28 GHz microwave heating.